EPA Greenlights Mississippi's Plan to Curb SO2 Air Pollution Drift
Published Date: 8/27/2026
Proposed Rule
Summary
Pursuant to the Federal Clean Air Act (CAA or the Act), the U.S. Environmental Protection Agency (EPA or Agency) is proposing to approve a State Implementation Plan (SIP) revision submitted by the State of Mississippi, through the Mississippi Department of Environmental Quality (MDEQ), on January 27, 2022, for the purpose of complying with the "good neighbor" provision of the CAA for the 2010 1-hour sulfur dioxide (SO<INF>2</INF>) primary National Ambient Air Quality Standard (NAAQS). The good neighbor provision requires each State's implementation plan to contain adequate provisions prohibiting the interstate transport of air pollution in amounts that will contribute significantly to nonattainment, or interfere with maintenance, of a NAAQS in any other State. In this proposed rulemaking, the EPA is proposing to determine that Mississippi will not contribute significantly to nonattainment or interfere with maintenance of the 2010 1-hour SO<INF>2</INF> primary NAAQS in any other State. Therefore, the EPA is proposing to approve the January 27, 2022, SIP revision as meeting the requirements of the good neighbor provision for the 2010 1-hour SO<INF>2</INF> primary NAAQS.
Analyzed Economic Effects
1 provisions identified: 1 benefits, 0 costs, 0 mixed.
EPA Proposes Approval of Mississippi SO2 SIP
If you live in Mississippi, Alabama, Tennessee, or Louisiana, the EPA is proposing to approve Mississippi's State Implementation Plan (submitted January 27, 2022) for the 2010 1-hour sulfur dioxide (SO2) standard (75 parts per billion). The EPA's proposal says Mississippi will not significantly contribute to nonattainment or interfere with maintenance of the 2010 1-hour SO2 NAAQS in any other State, based on analyses that focused on sources within 50 kilometers of the State border and sources emitting over 100 tons per year. The Federal Register publication is August 27, 2026 and comments are due September 17, 2026.
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